Estimation of Mixing Ratio for Saturated Air over Water

Abstract

The role that water vapor plays in atmospheric phenomena is extremely important. Saturation of moist air at a given temperature and pressure occurs if its mixing ratio is such that the moist air can coexist in a stable condition with an associated condensed phase at the same temperature and pressure. The saturation mixing ratio is useful to calculate the relative humidity which is a ratio, expressed in percent, of the amount of water vapor in the air (actual mixing ratio) compared to the amount of water vapor the air can hold (saturation mixing ratio). In this work, an attempt has been made to develop a simple-to-use Arrhenius-type function to estimate the mixing ratio for saturated air over water as a function of pressure and temperature. Estimations have been found to be in excellent agreement with the data reported in the literature, with the average absolute deviation being around 0.4 %.

Estimation and variation of saturation mixing ratio and mixing ratio over Potiskum, Nigeria

“…The result in this study is in agreement with that reported by Bahadori et al (2012) as depicted in Fgure 1 and 2 of their study where it was also shown that as the saturation mixing ratio increases the temperature increases as well and vice versa. Also, as reported by Przybylak, (2016) and Vicente-Serrano et al (2016) where similar observation was testified.…”

“…Saturation of moist air at a given temperature and pressure occurs if its mixing ratio is such that the moist air can coexist in a stable condition with an associated condensed phase at the same temperature and pressure (Bahadori et al, 2012). The saturation mixing ratio is useful to calculate the relative humidity which is a ratio, expressed in percent, of the amount of water vapour in the air (actual mixing ratio) compared to the amount of water vapour the air can hold (saturation mixing ratio) (Bahadori et al, 2012). The vapour pressure (e) of water in the atmosphere is independent of the presence of other gases, i.e., it is the partial pressure due to water vapour.…”

“…Below 0 °C, the saturation vapour pressure over supercooled water (𝑒 𝑤 ) is different from that over ice (𝑒 𝑖 ) (Burger, 1975;Singh et al, 2002;Hasan, 2010;Bahadori, 2011 andHasan, 2012). Bahadori et al (2012) attempted to develop a simple-to-use Arrhenius-type function to estimate the mixing ratio for saturated air over water as a function of pressure and temperature. They reported that the estimations were found to be in excellent agreement with the data reported in the literature, with the average absolute deviation being around 0.4 %.…”

Impact of Lockdown Measures during COVID-19 Pandemic on Water Vapors in Subtemperate and Subtropical Zones of Jammu Region, Jammu & Kashmir Union Territory, India

“…Saturated mixing ratio refers to the mass of water vapor that can be held in kg of dry air at saturation. The relation between air temperature and saturated mixing ratio is exponential which states saturated mixing ratio is a function of temperature at constant air pressure [18]. However, in subtropical zone with decrease in temperature values, the saturated mixing ratio is also lowered but in subtemperate zone where temperature is lowered but air pressure has decreased with increase in altitude leading to rise in parcels of unsaturated air forcing cloud formation and rains making air saturated and increase in saturated mixing ratio [19].…”